Sulfonated melamine-formaldehyde polycondensate water reducer and preparation method thereof

A technology of sulfonated melamine and formaldehyde polycondensate, which is applied in the field of sulfonated melamine-formaldehyde polycondensate water reducer and its preparation, can solve problems such as failure to achieve ideal molecular weight, small molecular weight of polycondensate, hinder polycondensation, etc., and achieve relief from excessive Influence, reduce the amount of acid and alkali used, improve the effect of thermal stability

Active Publication Date: 2012-01-04
JIANGSU SOBUTE NEW MATERIALS +2
View PDF5 Cites 12 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The limitation of this process is that when the degree of sulfonation of melamine is high, it will hinder its polycondensation, and finally the molecular weight of the polycondensate is small, which cannot reach the ideal molecular weight for the best dispersion effect.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Sulfonated melamine-formaldehyde polycondensate water reducer and preparation method thereof
  • Sulfonated melamine-formaldehyde polycondensate water reducer and preparation method thereof
  • Sulfonated melamine-formaldehyde polycondensate water reducer and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0037] (1) One sulfonation reaction

[0038] Put 63g (0.50mol) of melamine, 47.5g (0.25mol) of sodium metabisulfite, 10.0g of 30% sodium hydroxide solution and 190g of water into a 500ml flask, start the mechanical stirring, and raise the temperature to 80°C. 121.6 g of 37% formaldehyde solution (containing 1.50 mol of formaldehyde) was added dropwise to the reaction system at a constant speed within 15 minutes, and the pH value was measured to be 11-12 after the addition was completed. The reaction was continued at 80°C for 2 hours.

[0039] (2) Condensation reaction

[0040] 10.0 g of 30% sulfuric acid aqueous solution was added to adjust the pH of the system to 5-6, and the reaction was maintained at 80° C. for 2 hours. The weight-average molecular weight of the polycondensate was determined to be 58,000 by aqueous gel chromatography.

[0041] (3) Secondary sulfonation reaction

[0042] Add 5.0 g of 30% sodium hydroxide solution to adjust the pH value of the system to 8-9....

Embodiment 2

[0044] (1) One sulfonation reaction

[0045] Put 63g (0.50mol) of melamine, 67.6g (0.65mol) of sodium bisulfite, 12.0g of 30% sodium hydroxide solution and 140g of water into a 500ml flask, start the mechanical stirring, and raise the temperature to 90°C. 154.0 g of 37% formaldehyde solution (containing 1.90 mol of formaldehyde) was added dropwise to the reaction system at a constant speed within 40 minutes, and the pH value was measured to be 11-12 after the dropwise addition was completed. The reaction was continued at 90°C for 1 hour.

[0046] (2) Condensation reaction

[0047] 15.0 g of 30% sulfuric acid aqueous solution was added to adjust the pH of the system to 4-5, and the reaction was maintained at 90° C. for 0.5 hours. The weight average molecular weight of the polycondensate was determined to be 48,000 by aqueous gel chromatography.

[0048] (3) Secondary sulfonation reaction

[0049] Add 5.0 g of 30% sodium hydroxide solution to adjust the pH value of the system...

Embodiment 3

[0051] (1) One sulfonation reaction

[0052] Put 63g (0.50mol) of melamine, 75.6g (0.60mol) of sodium sulfite, 2.0g of 30% sodium hydroxide solution and 450g of water into a 1L flask, start the mechanical stirring, and raise the temperature to 70°C. 137.8 g of 37% formaldehyde solution (containing 1.70 mol of formaldehyde) was added dropwise to the reaction system at a constant speed within 60 minutes, and the pH value was measured to be 11-12 after the addition was completed. The reaction was continued at 70°C for 3 hours.

[0053] (2) Condensation reaction

[0054] 15.0 g of 30% sulfuric acid aqueous solution was added to adjust the pH of the system to 4-5, and the reaction was maintained at 70° C. for 2 hours. The weight-average molecular weight of the polycondensate was determined to be 52,000 by aqueous gel chromatography.

[0055] (3) Secondary sulfonation reaction

[0056] Add 11.0 g of 30% sodium hydroxide solution to adjust the pH value of the system to 8-9. Add 2...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a sulfonated melamine-formaldehyde polycondensate water reducer and a preparation method thereof. The preparation method for the sulfonated melamine-formaldehyde polycondensate water reducer comprises the following steps of: (1) primary sulfonation reaction, namely performing primary sulfonation reaction on melamine, a first part of formaldehyde and a first part of sulfite sulfonating agent, wherein a molar ratio of SO32- provided by the melamine, the first part of formaldehyde and the first part of sulfite sulfonating agent is 1:(3.0-4.0):(1.0-1.5); (2) condensation reaction; and (3) secondary sulfonation reaction, namely adjusting the pH value to be 8-9, adding a second part of formaldehyde and a second part of sulfite sulfonating agent, ensuring that a molar ratio of SO32- provided by the melamine added in the step (1), the second part of formaldehyde and the second part of sulfite sulfonating agent is 1:(1.0-3.0):(0.2-1.0), adjusting the pH value of the reaction, and performing the secondary sulfonation reaction.

Description

technical field [0001] The invention relates to a sulfonated melamine-formaldehyde condensation polymer water reducer and a preparation method thereof. Background technique [0002] Sulfonated melamine-formaldehyde polycondensate superplasticizer belongs to a kind of water-soluble polymer resin. When used in concrete mixture, it has good dispersion of cement, remarkable early strength effect, good surface finish of concrete, and basically does not affect the setting time of concrete. And the characteristics of air content, especially suitable for the production of prefabricated concrete. Although this type of water reducer was successfully developed by West Germany as early as the 1960s, Japan and other countries further developed it on the basis of the introduction of West German technology. Although there are many literature reports on sulfonated melamine-formaldehyde polycondensate water reducer, the SO in the sulfonated agent in these reports 3 2- The molar ratio of m...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C08G12/40C08G12/32C04B24/16C04B103/30
Inventor 刘加平乔敏冉千平缪昌文刘金芝张建纲毛永琳
Owner JIANGSU SOBUTE NEW MATERIALS
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap